In 1513, Vasco Nunez de Balboa's discovery of the Pacific coast of Panama soon had merchants and empire-builders dreaming of a shortcut that would enable ships to sail westward from the Atlantic to the Pacific without making the arduous, 12,000-mile journey around the tip of South America.

Over the next two centuries, visionaries ranging from Benjamin Franklin to the German philosopher Goethe advocated the digging of a channel. After Latin America won independence from Spain in the 1820s, the revolutionary hero Simon Bolivar hired engineers to map a possible canal route. Some, such as German explorer Heinrich Alexander von Humboldt, argued that Panama was too wild and mountainous, and that Nicaragua would be a better location. U.S. Army Col. Charles Biddle, sent by President Andrew Jackson to Central America in 1835 to evaluate the matter, concluded after four days of hiking in the jungle that the impracticality of building a canal in Panama ought to be clear to anyone, "whether of common or uncommon sense." Nevertheless, over the next 40 years, a parade of speculators dreamed up canal-building schemes.

Statistics:
Estimated Cost in 1785: $200,000
Estimated Cost in 1843: $26 million
Estimated Cost in 1850: $60 million
 

French entrepreneur Ferdinand de Lesseps envisioned La Grande Tranchee ("the great trench") as a sea-level canal without locks, akin to the one built by the French at Suez. Unfortunately, the verdant jungles and mountainous terrain of Panama proved far-more difficult environments to conquer than the desert. The Compagnie Universelle du Canal Interoceanique was disorganized from the start, starting without a blueprint and laying down railroad tracks that didn't fit the gauge of the existing Panama railroad. By 1883, the French had 20,000 laborers at work, but they had trouble digging up even a 10th of the 2,000,000 cubic meters of earth called for in the company's projections, and the work was plagued by disasters. The French canal-builders' quick-and-dirty excavation method of chopping the tops off hills in their path and piling the dirt on either side led to disastrous landslides.

Disease was an even bigger foe: By 1884, yellow fever was killing 200 laborers each month. By 1887, the French had picked up the pace, but they were running out of money. The project collapsed two years later after a stock lottery garnered only a fraction of the $100 million needed to continue.

Statistics:
Number of snow shovels inexplicably ordered by the French: 10,000
Earth moved to date: 66,744,000 cubic yards
Total cost to date: approximately $30 million
 

In 1898, with the United States and Spain on the brink of war, the Oregon -- the U.S. Navy's first true battleship -- took 67 days to rush back from San Francisco to the Caribbean. That stuck in the mind of Theodore Roosevelt. When William McKinley's assassination made TR president in 1901, he vowed to build a canal -- not for commerce, like the French, but to ensure that U.S. naval power could dominate two oceans. He favored Nicaragua at first but abruptly changed his mind to Colombian-owned Panama when the French made it known they were willing to unload their partly dug ditch at a bargain price of $40 million. A skeptical Congress was eventually swayed with a high-powered lobbying campaign by France's former chief engineer Philippe Bunau-Varilla, who'd made it his mission to see the project completed. At the last moment, Colombia nearly threw a wrench in the deal by insisting that the United States pay for the right to dig on Colombian soil, but the White House and the Panama Canal lobby were not to be stopped. In late 1903, revolutionaries organized and financed by Bunau-Varilla staged a coup on the Isthmus, and a U.S. warship suddenly steamed into Panama City's harbor to deter the Colombians from suppressing the revolt. The new, independent nation of Panama quickly gave the United States the go-ahead. The Americans, however, could only use a portion of what the French had excavated. Over 48,000,000 cubic yards of earth moved through French back-breaking labor was useless as the Americans began to dig.

Statistics:
Number of persons killed in the Panamanian revolution: 1 (also 1 donkey)
Earth moved to date: 29,700,000 cubic yards
Total cost to date: approximately $337 million
 

In 1905, workers on the American canal project began to fall ill with yellow fever, the deadly disease that had decimated the French work force 20 years before. But the Americans, unlike the French, had a way to fight the disease.

In 1900, U.S. Army tropical disease expert Walter Reed proved what previous scientists had suspected -- that the fever was transmitted not by poor sanitation or contact with infected people, but by the female member of the mosquito species Stegomyia fasciata. The following year, in fever-ridden Havana, a Reed protégé named Col. William C. Gorgas staged a successful campaign to eradicate the mosquitoes; yellow fever disappeared.

Gorgas was assigned to Panama but ran into stiff resistance at first from budget-conscious bureaucrats -- who thought, incredibly, that he wanted tons of old newspapers, which he needed to seal windows for fumigating, as reading material for fever patients. Finally, in April 1905, after the fever outbreak had killed 47 workers, Gorgas got the go-ahead and funding he needed. Over the next few months, he installed $90,000 worth of wire screens on windows and sent teams of health workers on a door-to-door search for mosquitoes and their eggs. They fumigated houses -- several times if necessary -- and enforced a ban on the old Panamanian custom of keeping water indoors in uncovered containers. They traced the movements of victims to determine where they'd been infected. By December, yellow fever had vanished from the Canal Zone.

Statistics:
Supplies required for eradication of yellow fever:
Gallons of kerosene oil per month: 50,000; Tons of Sulfur: 300; Brooms: 1,000; Fumigation pots: 1,200
Total cost to date: approximately $407 million
 

The American canal builders started out almost as badly as the French: the first wave of laborers had to drive railroad spikes with axes because they hadn't been given sledgehammers. The Roosevelt administration appointed the illustrious John Findley Wallace as head engineer. This former president of the American Society of Civil Engineers was accustomed to building low-stress projects in urban areas, and he left after just a year to take a job in the private sector.

His successor, John Stevens, lacked a college degree, but he was a rough-hewn outdoorsman who'd extended the Great Northern Railroad through the Rockies, using a mountain pass he himself had discovered. Stevens stopped digging and spent two years methodically building the infrastructure needed to stage the massive project -- everything from sewers for Panama's two cities to a bakery to supply his workers with bread. By early 1907, when Stevens was ready to resume digging, the effort was so well-organized that before long the workers were excavating 500,000 cubic yards of soil a month, more than double the French's best performance. Stevens astutely realized that a sea-level canal would be too difficult, and convinced Roosevelt to opt for a canal with locks instead.

Statistics:
Earth moved to date: 46,000,000 cubic yards
Total cost to date: approximately $437 million
 

In 1907, chief engineer Stevens, tough as he was, began to crack under the pressure; he wrote a stinging letter to President Roosevelt accusing bureaucrats and politicians of stabbing him in the back and complaining that, "to me, the canal is only a big ditch." Roosevelt quickly replaced him with Army officer Col. George W. Goethals, who led the project through its most arduous stages, including the excavation of the mountainous Culebra Cut. During this stage of excavation workers had to brave massive landslides that sometimes set work back for months at a time.

Even so, Goethals took the efficient system that Stevens had built and pushed it to ever-astonishing levels of performance. From 1907 to 1914, Goethals' work force excavated nearly 215,000,000 cubic yards of earth, nearly three times what the French had accomplished. Goethals also supervised the construction of the locks advocated by Stevens, the biggest and most technologically advanced devices of their kind ever built. In August 1914, a cement boat, the Cristobal, made the first actual passage from the Atlantic to the Pacific, with Philippe Bunau-Varilla onboard. Two weeks later, on August 15, a ship named Ancon sailed on the first official interocean transit through the Panama Canal.

Statistics:
Estimated height of earth excavated if it were piled: one city block wide by 19 miles high
Earth moved to date: 262,000,000 cubic yards
Total cost to date: approximately $639 million